Using apps like Facebook, Email and Modern-based web browsers,such as Chrome, can be really frustrating. a simple misclick or wider mouse movement and ~BAM~ your app just got closed by a mischievous title bar. As a laptop user, this is a constant issue...
Also, the space hogging Start Button and the discrepand contextual right-click menu at the Start Screen are issues that should be addressed.
Maybe simple system flags that can be set somewhere, just as the "go to desktop when all apps are closed" option Microsoft added to the taskbar configurations.
Seriously, I never thought inflexible users would manage to break an operating system that had just evolved to be like its user-friendly peers (I'm talking about how close Windows 8 brought me to my previous Ubuntu and OSX experiences).